Update prost-build requirement from 0.12.2 to 0.13.0

Updates the requirements on [prost-build](https://github.com/tokio-rs/prost) to permit the latest version.
- [Release notes](https://github.com/tokio-rs/prost/releases)
- [Changelog](https://github.com/tokio-rs/prost/blob/master/CHANGELOG.md)
- [Commits](tokio-rs/prost@v0.12.2...v0.13.0)

---
updated-dependencies:
- dependency-name: prost-build
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

save/gen-protos/Cargo.toml

@@ -5,4 +5,4 @@ edition = "2021"
 publish = false
 
 [dependencies]
-prost-build = "0.12.2"
+prost-build = "0.13.0"